The human head being an organic appendage, varies significantly in size and shape, thus making it difficult to design eyewear which may accommodate a wide cross section of the population. One method which has been designed to accommodate a wide cross section is that originally made for the military. "RAY-BAN AVIATOR" sunglasses, made by Bausch and Lomb, Inc. are an example. Bausch and Lomb, Inc. manufacturers standard glasses having a simple frame comprised of wrap-around temple portions. Each wrap-around temple portion includes a substantially straight portion and a flexible, wrap-around, curved portion. One end of the straight portion pivotally connects, via a hinged end, to the lens frame. At another end of the straight portion, the flexible, curved portion attaches. The curved portion curves downward such that when the eyewear is worn, the ends of the wrap-around portion wraps around the ear securely holding the eyewear in place. The curved portion is made of a resilient flexible material which has a memory that causes it to bias to its original, most tightly curved position when removed from the wearer.
This wrap-around system has proven durable, and effective to securely hold the eyewear in place during the frequent quick side-to-side, up-and-down (and combinations thereof) movements of the head typically required military observation or combat, and, of course, during sporting activity. However, at least one significant disadvantage exists. The wrap-around portions tend to wear into the flesh of the wearer's ear, causing discomfort, pain and general annoyance. Proper initial fitting may help alleviate these problems, but cannot accommodate the variety of wearers which may borrow the same pair of eyewear, common with nonprescription sunglasses, for example. Initial fitting for comfort does not usually result in the highest curvature, desirable when highly active sports are engaged in--a situation in which the user desires the maximum holding power. When the eyewear is fit, the temples are usually expanded and the curvature of the curved portion reduced in order to relieve the chaffing pressure on the ears. The maximum holding ability, which is lost upon initial adjustment and fitting, cannot be regained without completely refitting the eyewear. This can be time consuming, inconvenient and may also result in premature failure of the temple portions due to excessive fatigue brought on by repeated cycles of adjustment.
Attempts have been made to improve adjustability and alleviate the discomfort associated with wrap-around temple portions, but these have discarded the early wrap-around temple portions in favor of more complicated but more readily adjustable methods. Such alternative methods depart from the "authentic military" design of early sunglasses.
Further, "RAY-BAN AVIATOR"-type glasses with flexible, curved portions cannot be used with a full face motorcycle helmet. This is because the extremely flexible curved portions of the temple portions cannot be wrapped around the ears unless adequate access is provided such that the fingers of the hand are free to guide the curved portions around the ears. No full-face motorcycle helmet provides such access.
A need therefore exists for a means to provide adjustability to the more conventional wrap-around type temple portion (e.g., "RAY-BAN AVIATOR"-type temple portions) which can be made at minimal cost and yet provide for nearly infinite variability of the effective length and curvature of the temple portions, as well as permit use in full-face motorcycle helmets.